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A047609
Numbers that are congruent to {0, 4, 5} mod 8.
1
0, 4, 5, 8, 12, 13, 16, 20, 21, 24, 28, 29, 32, 36, 37, 40, 44, 45, 48, 52, 53, 56, 60, 61, 64, 68, 69, 72, 76, 77, 80, 84, 85, 88, 92, 93, 96, 100, 101, 104, 108, 109, 112, 116, 117, 120, 124, 125, 128, 132, 133, 136, 140, 141, 144, 148, 149, 152, 156, 157
OFFSET
1,2
FORMULA
From Wesley Ivan Hurt, Jun 09 2016: (Start)
G.f.: x^2*(4+x+3*x^2)/((x-1)^2*(1+x+x^2)).
a(n) = a(n-1) + a(n-3) - a(n-4) for n>4.
a(n) = (24*n-21-6*cos(2*n*Pi/3)-4*sqrt(3)*sin(2*n*Pi/3))/9.
a(3k) = 8k-3, a(3k-1) = 8k-4, a(3k-2) = 8k-8. (End)
MAPLE
A047609:=n->(24*n-21-6*cos(2*n*Pi/3)-4*sqrt(3)*sin(2*n*Pi/3))/9: seq(A047609(n), n=1..100); # Wesley Ivan Hurt, Jun 09 2016
MATHEMATICA
Select[Range[0, 150], MemberQ[{0, 4, 5}, Mod[#, 8]] &] (* Wesley Ivan Hurt, Jun 09 2016 *)
PROG
(Magma) [n : n in [0..150] | n mod 8 in [0, 4, 5]]; // Wesley Ivan Hurt, Jun 09 2016
CROSSREFS
Sequence in context: A130814 A183181 A310575 * A360993 A310576 A188095
KEYWORD
nonn,easy
STATUS
approved